SOLEPHEM(3)
NAME
solephem -- calculates various astronomical quantities for
the sun
SYNOPSIS
solephem(time,ephem)
TIME time;
double ephem[19];
DESCRIPTION
This procedure finds the ephemerides for the sun at the time
"time." Several quantities are computed and returned in the
array ephem. See the American Ephemeris and Nautical
Almanac and program comments for details of methods used.
Quantites computed:
ephem[ 1]: time used for computation
ephem[ 2]: t=time in centuries of 36525 days since 1900.0
ephem[ 3]: jd = Julian date
ephem[ 4]: st = Siderial time (within day)
ephem[ 5]: ra = right ascension (geometric)
ephem[ 6]: dec= declination (geometric)
ephem[ 7]: clong = geometric longitude
ephem[ 8]: l0=Carrington Longitude of disk central point
ephem[ 9]: b0 = latitude of central point of disk
ephem[10]: p=position angle of northern extremity of
rotation axis -- to east from north in sky
ephem[11]: r = true distance to sun in AU
ephem[12]: rsun=true semi-diameter of sun(arc-sec)
uncorrected for irradiance (d.f. AENA pg.541)
ephem[13]: vearth=angular velocity of earth * 1AU (m/s)
ephem[14]: eot = equation of time
ephem[15]: b0 wobble (m/s)
ephem[16]: phi = aux angle for deltav
ephem[17]: sin(p)
ephem[18]: cos(p)
FILES
/usr/local/lib/libastro.a ( -lastro )
/usr/src/local/astro/solephem.c
SEE ALSO
date (on local)
DIAGNOSTICS
none or obvious
BUGS
Note that because of the AENA formulae used, some of the
numbers do not make sense if a time before the middle of the
20th century is given.